JP6391471B2 - Wafer generation method - Google Patents

Wafer generation method Download PDF

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Publication number
JP6391471B2
JP6391471B2 JP2015001040A JP2015001040A JP6391471B2 JP 6391471 B2 JP6391471 B2 JP 6391471B2 JP 2015001040 A JP2015001040 A JP 2015001040A JP 2015001040 A JP2015001040 A JP 2015001040A JP 6391471 B2 JP6391471 B2 JP 6391471B2
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wafer
single crystal
surface
laser beam
ingot
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JP2016124015A (en
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平田 和也
和也 平田
高橋 邦充
邦充 高橋
曜子 西野
曜子 西野
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株式会社ディスコ
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B28WORKING CEMENT, CLAY, OR STONE
    • B28DWORKING STONE OR STONE-LIKE MATERIALS
    • B28D5/00Fine working of gems, jewels, crystals, e.g. of semiconductor material; apparatus or devices therefor
    • B28D5/0005Fine working of gems, jewels, crystals, e.g. of semiconductor material; apparatus or devices therefor by breaking, e.g. dicing
    • B28D5/0011Fine working of gems, jewels, crystals, e.g. of semiconductor material; apparatus or devices therefor by breaking, e.g. dicing with preliminary treatment, e.g. weakening by scoring
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/0006Working by laser beam, e.g. welding, cutting or boring taking account of the properties of the material involved
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/50Working by transmitting the laser beam through or within the workpiece
    • B23K26/53Working by transmitting the laser beam through or within the workpiece for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks
    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10Inorganic compounds or compositions
    • C30B29/36Carbides
    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10Inorganic compounds or compositions
    • C30B29/40AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
    • C30B29/403AIII-nitrides
    • C30B29/406Gallium nitride
    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B33/00After-treatment of single crystals or homogeneous polycrystalline material with defined structure
    • C30B33/06Joining of crystals
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/304Mechanical treatment, e.g. grinding, polishing, cutting
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2103/00Materials to be soldered, welded or cut
    • B23K2103/50Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
    • B23K2103/56Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26 semiconducting

Description

  The present invention relates to a method for producing a wafer in which a hexagonal single crystal ingot is sliced into wafers.

  Various devices such as IC and LSI are formed in a region partitioned by a plurality of scheduled division lines on a functional layer laminated on the surface of a wafer made of silicon or the like. Then, the wafer division line is processed by a processing device such as a cutting device or a laser processing device, the wafer is divided into individual device chips, and the divided device chips are applied to various electronic devices such as mobile phones and personal computers. Widely used.

  In addition, a power device or an optical device such as an LED or LD has a functional layer laminated on the surface of a wafer made of a hexagonal single crystal such as SiC or GaN, and a plurality of layers formed in a lattice shape on the laminated functional layer. It is divided and formed by a predetermined dividing line.

  The wafer on which the device is formed is generally produced by slicing an ingot with a wire saw, and the front and back surfaces of the sliced wafer are polished to a mirror finish (see, for example, Japanese Patent Application Laid-Open No. 2000-94221).

  In this wire saw, a single wire such as a piano wire having a diameter of about 100 to 300 μm is usually wound around a number of grooves provided on two to four spacing auxiliary rollers and arranged parallel to each other at a constant pitch. An ingot is sliced into a plurality of wafers by running the wire in a certain direction or in both directions.

  However, when the ingot is cut with a wire saw and the front and back surfaces are polished to produce a wafer, 70 to 80% of the ingot is discarded, which is uneconomical. In particular, hexagonal single crystal ingots such as SiC and GaN have high Mohs hardness, are difficult to cut with a wire saw, take a considerable amount of time, have poor productivity, and have a problem in efficiently producing a wafer. Yes.

In order to solve these problems, the focusing point of a laser beam having a wavelength that is transmissive to a hexagonal single crystal such as SiC is positioned inside the hexagonal single crystal ingot and irradiated to improve the cutting plane. forming a quality layer and cracks, by cleaving the wafer by applying an external force along the planned cutting surface reforming layer and cracks were formed, a technique for separating a wafer from the ingot Patent 2013-49 1 61 No. It is described in the publication.

  In the technique described in this publication, the condensing point of the pulse laser beam is set so that the first irradiation point of the pulse laser beam and the second irradiation point closest to the first irradiation point are in a predetermined position. Is irradiated spirally along the planned cutting surface, or is irradiated linearly to form a very high-density modified layer and cracks on the planned cutting surface of the ingot.

JP 2000-94221 A JP 2013-49461 A

  However, in the ingot cutting method described in Patent Document 2, the laser beam irradiation method is spiral or linear with respect to the ingot, and in the case of the linear shape, the direction in which the laser beam is scanned is not defined at all.

  In the ingot cutting method described in Patent Document 2, the pitch between the first irradiation point of the laser beam and the second irradiation point closest to the first irradiation point is set to 1 μm to 10 μm. . This pitch is a pitch at which cracks generated from the modified layer extend.

  Since the pitch when irradiating the laser beam is very small in this way, it is necessary to irradiate the laser beam at a very small pitch interval, regardless of whether the laser beam irradiation method is spiral or linear. There is a problem that productivity is not sufficiently improved.

  The present invention has been made in view of these points, and an object of the present invention is to provide a wafer generation method capable of efficiently generating a wafer from an ingot.

  According to the present invention, the first surface, the second surface opposite to the first surface, the c-axis extending from the first surface to the second surface, and the c-plane orthogonal to the c-axis A wafer generating method for generating a wafer from a hexagonal single crystal ingot having: a condensing point of a laser beam having a wavelength transparent to the hexagonal single crystal ingot is generated from the first surface It is positioned at a depth corresponding to the thickness of the wafer, and the laser beam is applied to the first surface by moving the focusing point and the hexagonal single crystal ingot relative to each other. A separation origin forming step for forming a separation starting point by forming a parallel modified layer and a crack extending from the modified layer, and a plate corresponding to the thickness of the wafer from the separation starting point after performing the separation starting point forming step The hexagonal crystal is peeled off from the hexagonal single crystal ingot. A separation step of forming a crystal wafer, wherein the c-axis is inclined by an off-angle with respect to the normal of the first surface, and the first surface and the c surface A modified layer forming step of forming a linear modified layer by relatively moving the condensing point of the laser beam in a direction orthogonal to the direction in which the off angle is formed, and the off angle is formed An index step for indexing a predetermined amount by relatively moving the condensing point in the direction, and in the wafer peeling step, a hexagonal single crystal ingot is immersed in water and ultrasonic waves are applied to form a plate-like material. Is produced from the hexagonal single crystal ingot to produce a hexagonal single crystal wafer.

  According to the method for producing a wafer of the present invention, the modified layer is formed at a predetermined depth from the first surface, and cracks propagate along the c-plane on both sides of the modified layer. When the hexagonal single crystal ingot is immersed in water and ultrasonic waves are applied, the plate-like material corresponding to the thickness of the wafer is separated from the separation starting point. It can be easily peeled off to form a hexagonal single crystal wafer.

  Therefore, the productivity can be sufficiently improved, and the amount of ingots to be discarded can be sufficiently reduced and can be suppressed to about 30%.

It is a perspective view of the laser processing apparatus suitable for implementing the production | generation method of the wafer of this invention. It is a block diagram of a laser beam generation unit. FIG. 3A is a perspective view of a hexagonal single crystal ingot, and FIG. 3B is a front view thereof. It is a perspective view explaining a separation starting point formation step. It is a top view of a hexagonal single crystal ingot. It is typical sectional drawing explaining the modified layer formation step. It is a schematic plan view explaining a modified layer formation step. FIG. 8A is a schematic plan view for explaining the index step, and FIG. 8B is a schematic plan view for explaining the index amount. It is a perspective view explaining a wafer peeling step. 1 is a perspective view of a produced hexagonal single crystal wafer. FIG. It is explanatory drawing of the separation starting point formation step which concerns on this invention embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, there is shown a perspective view of a laser processing apparatus 2 suitable for carrying out the wafer production method of the present invention. The laser processing apparatus 2 includes a first slide block 6 mounted on a stationary base 4 so as to be movable in the X-axis direction.

  The first slide block 6 is moved in the machining feed direction, that is, the X-axis direction along the pair of guide rails 14 by the machining feed mechanism 12 including the ball screw 8 and the pulse motor 10.

  A second slide block 16 is mounted on the first slide block 6 so as to be movable in the Y-axis direction. That is, the second slide block 16 is moved along the pair of guide rails 24 by the index feed mechanism 22 including the ball screw 18 and the pulse motor 20 in the index feed direction, that is, the Y-axis direction.

  A support table 26 is mounted on the second slide block 16. The support table 26 can be moved in the X-axis direction and the Y-axis direction by the machining feed mechanism 12 and the index feed mechanism 22 and is rotated by a motor accommodated in the second slide block 16.

  A column 28 is erected on the stationary base 4, and a laser beam irradiation mechanism (laser beam irradiation means) 30 is attached to the column 28. The laser beam irradiation mechanism 30 includes a laser beam generation unit 34 shown in FIG. 2 housed in a casing 32, and a condenser (laser head) 36 attached to the tip of the casing 32. An imaging unit 38 having a microscope and a camera aligned with the condenser 36 and in the X-axis direction is attached to the tip of the casing 32.

  As shown in FIG. 2, the laser beam generation unit 34 includes a laser oscillator 40 that oscillates a YAG laser or a YVO4 laser, a repetition frequency setting unit 42, a pulse width adjustment unit 44, and a power adjustment unit 46. . Although not particularly shown, the laser oscillator 40 has a Brewster window, and the laser beam emitted from the laser oscillator 40 is a linearly polarized laser beam.

  The pulse laser beam adjusted to a predetermined power by the power adjusting means 46 of the laser beam generating unit 34 is reflected by the mirror 48 of the condenser 36 and is further fixed on the support table 26 by the condenser lens 50. A condensing point is positioned inside a certain hexagonal single crystal ingot 11 and irradiated.

  Referring to FIG. 3A, a perspective view of a hexagonal single crystal ingot 11 that is a processing object is shown. FIG. 3B is a front view of the hexagonal single crystal ingot 11 shown in FIG. The hexagonal single crystal ingot (hereinafter sometimes simply referred to as ingot) 11 is composed of a SiC single crystal ingot or a GaN single crystal ingot.

  The ingot 11 has a first surface (upper surface) 11a and a second surface (back surface) 11b opposite to the first surface 11a. The surface 11a of the ingot 11 is polished to a mirror surface to be a laser beam irradiation surface.

  The ingot 11 has a first orientation flat 13 and a second orientation flat 15 orthogonal to the first orientation flat 13. The length of the first orientation flat 13 is longer than the length of the second orientation flat 15.

  The ingot 11 has a c-axis 19 inclined at an off angle α in the direction of the second orientation flat 15 with respect to the perpendicular 17 of the surface 11 a and a c-plane 21 orthogonal to the c-axis 19. The c-plane 21 is inclined with respect to the surface 11 a of the ingot 11 by an off angle α. In general, in the hexagonal single crystal ingot 11, the direction orthogonal to the extension direction of the short second orientation flat 15 is the c-axis inclination direction.

  The c-plane 21 is set innumerably in the ingot 11 at the molecular level of the ingot 11. In the present embodiment, the off angle α is set to 4 °. However, the off angle α is not limited to 4 °. For example, the ingot 11 can be manufactured by freely setting in the range of 1 ° to 6 °.

  Referring to FIG. 1 again, a column 52 is fixed to the left side of the stationary base 4, and a pressing mechanism 54 is mounted on the column 52 through an opening 53 formed in the column 52 so as to be movable in the vertical direction. Has been.

  In the wafer production method of the present embodiment, as shown in FIG. 4, the ingot 11 is fixed on the support table 26 with, for example, wax or an adhesive so that the second orientation flat 15 of the ingot 11 is aligned in the X-axis direction. To do.

  That is, as shown in FIG. 5, the direction Y1 in which the off-angle α is formed, in other words, perpendicular to the perpendicular 17 of the surface 11a of the ingot 11 and the direction where the intersection 19a with the surface 11a of the c-axis 19 exists. The ingot 11 is fixed to the support table 26 by aligning the direction, that is, the direction of arrow A with the X axis.

  Thereby, the laser beam is scanned along the direction A orthogonal to the direction in which the off angle α is formed. In other words, the A direction orthogonal to the direction Y1 in which the off angle α is formed is the processing feed direction of the support table 26.

  In the wafer generation method of the present invention, it is important that the scanning direction of the laser beam emitted from the condenser 36 is the arrow A direction orthogonal to the direction Y1 in which the off angle α of the ingot 11 is formed.

  That is, according to the method for producing a wafer of the present invention, the crack propagating from the modified layer formed inside the ingot 11 is set along the c-plane 21 by setting the scanning direction of the laser beam to the above-described direction. It is characterized in that it has been found to extend very long.

  In the wafer generation method of the present embodiment, first, a condensing point of a laser beam having a wavelength (for example, a wavelength of 1064 nm) having transparency to the hexagonal single crystal ingot 11 fixed to the support table 26 is set to the first. The surface 11a is positioned at a depth corresponding to the thickness of the wafer produced from the surface (surface) 11a, and the surface 11a is irradiated with a laser beam by relatively moving the focusing point and the hexagonal single crystal ingot 11 to the surface 11a. A separation starting point forming step is performed in which the parallel modified layer 23 and the crack 25 propagating from the modified layer 23 along the c-plane 21 are formed to be a separation starting point.

  In this separation starting point forming step, the c-axis 19 is inclined by the off-angle α with respect to the perpendicular 17 of the surface 11a, and the direction perpendicular to the direction in which the off-angle α is formed between the c-plane 21 and the surface 11a, that is, FIG. A crack that propagates along the c-plane 21 from the modified layer 23 and the modified layer 23 to the inside of the ingot 11 by relatively moving the condensing point of the laser beam in the A direction that is orthogonal to the arrow Y1 direction And an index step for indexing a predetermined amount by relatively moving the condensing point in the direction in which the off-angle is formed, that is, the Y-axis direction, as shown in FIGS. Including.

  As shown in FIGS. 6 and 7, when the modified layer 23 is formed linearly in the X-axis direction, cracks 25 are propagated along the c-plane 21 from both sides of the modified layer 23. In the wafer generation method of the present embodiment, an index amount setting step for measuring the width of the crack 25 formed by propagating from the linear modified layer 23 in the c-plane direction and setting the index amount of the condensing point is performed. Including.

  In the index amount setting step, as shown in FIG. 6, when the width of the crack 25 that propagates from the straight modified layer 23 in the c-plane direction and is formed on one side of the modified layer 23 is W1, the index is set. The predetermined power W2 is set to W1 or more and 2W1 or less.

  Here, the laser processing method of a preferred embodiment is set as follows.

Light source: Nd: YAG pulse laser Wavelength: 1064 nm
Repetition frequency: 80 kHz
Average output: 3.2W
Pulse width: 4 ns
Spot diameter: 10 μm
Numerical aperture (NA) of condenser lens: 0.45
Index amount: 400 μm

  Under the laser processing conditions described above, in FIG. 6, the width W1 of the crack 25 propagating from the modified layer 23 along the c-plane is set to about 250 μm, and the index amount W2 is set to 400 μm.

  However, the average output of the laser beam is not limited to 3.2 W, and with the processing method of this embodiment, good results were obtained by setting the average output to 2 W to 4.5 W. When the average output was 2 W, the width W1 of the crack 25 was approximately 100 μm, and when the average output was 4.5 W, the width W1 of the crack 25 was approximately 350 μm.

  When the average output is less than 2 W and greater than 4.5 W, the good modified layer 23 cannot be formed inside the ingot 11, so the average output of the irradiated laser beam is 2 W to 4.5 W Within the range, in the present embodiment, the laser beam with an average output of 3.2 W was irradiated to the ingot 11. In FIG. 6, the depth D1 from the surface 11a of the condensing point which forms the modified layer 23 was set to 500 μm.

  Referring to FIG. 8A, a schematic diagram illustrating the scanning direction of the laser beam is shown. The separation starting point forming step is performed in the forward path X1 and the return path X2, and the condensing point of the laser beam in which the modified layer 23 is formed on the hexagonal single crystal ingot 11 in the forward path X1 is indexed by a predetermined amount, and then the hexagonal path in the return path X2 The modified layer 23 is formed on the crystal single crystal ingot 11.

  In the separation starting point forming step, when the predetermined amount to be indexed of the condensing point of the laser beam is set to W or more and 2 W or less, the condensing point of the laser beam is positioned on the hexagonal single crystal ingot 11 and the first modification is performed. It is preferable that the index amount of the condensing point until the quality layer 23 is formed is set to W or less.

  For example, as shown in FIG. 8B, when the predetermined amount for indexing the focal point of the laser beam is 400 μm, the index amount is 200 μm until the first modified layer 23 is formed on the ingot 11. Execute laser beam scanning multiple times.

  If the first laser beam scan is idle, and it is found that the modified layer 23 is first formed in the ingot 11, the index amount is set to 400 μm and the modified layer is formed in the ingot 11. 23 is formed.

  When the formation of the plurality of modified layers 23 and the cracks 25 extending from the modified layers 23 along the c-plane 21 at the position of the depth D1 of the entire region of the ingot 11 is completed while feeding the index by a predetermined amount as described above. Then, a wafer peeling step for separating the plate-like material corresponding to the thickness of the wafer to be formed from the separation starting point consisting of the modified layer 23 and the crack 25 from the hexagonal single crystal ingot 11 to generate the hexagonal single crystal wafer 27 is performed. To do.

  In this wafer peeling process, as shown in FIG. 9, an ultrasonic device 62 is placed in a water tank 60, and the hexagonal single crystal ingot 11 having a separation starting point is mounted on the ultrasonic device 62. Then, the water tank 60 is filled with pure water 64, the hexagonal single crystal ingot 11 is immersed in the pure water 64 of the water tank 60, and a voltage is applied to the ultrasonic device 62 to generate ultrasonic vibration of 40 kHz, for example.

  This ultrasonic vibration is transmitted to the hexagonal single crystal ingot 11, and the plate-like material corresponding to the thickness of the wafer is peeled from the separation starting point formed on the ingot 11, and the hexagonal single crystal ingot 11 is shown in FIG. A hexagonal single crystal wafer 27 can be produced. In addition, the container which accommodates the pure water 64 is not limited to the water tank 60, Of course, another container can also be used.

  As the ultrasonic device 62 that generates ultrasonic vibrations, for example, an AS ultrasonic cleaner US-2R provided by AS ONE Corporation can be used. The ultrasonic device 62 can generate 40 kHz ultrasonic vibration at an output of 80 W. The ultrasonic vibration applied in the wafer peeling step is preferably 30 kHz to 50 kHz, and more preferably 35 kHz to 45 kHz.

  Next, the separation starting point forming step according to the embodiment of the present invention will be described in detail with reference to FIG. As shown in FIG. 11 (A), when the condensing point P of the laser beam LB is positioned at the depth of the wafer to be generated and the surface 11a of the ingot 11 is irradiated with the laser beam LB, the laser beam LB is modified around the condensing point P. As the layer 23 is formed, cracks 25 are formed radially from the periphery of the modified layer 23 along the c-plane.

  That is, when the laser beam LB is irradiated once, as shown in FIG. 11B, a modified layer 23 and a crack 25 propagating from the modified layer 23 are formed around the modified layer 23 along the c-plane. The In the separation starting point forming step of the present embodiment, the step of positioning the condensing point P on the formed modified layer 23 and irradiating the laser beam is repeated a plurality of times.

  In this laser beam irradiation step, after the laser beam is scanned once from end to end of the ingot 11, the laser beam scan is repeated a plurality of times at the same repetition frequency and processing feed rate as the previous time.

  When the laser beam is scanned about 5 to 7 times, and the laser beam is irradiated with each modified layer 23 positioned at the focal point of the laser beam, as shown in FIG. The cracks 25 are separated and the cracks 25 on both sides of the modified layer 23 are connected.

  Thus, when the crack 25 and the modified layer 23 are separated from each other and the cracks are connected to each other, the peeling step can be carried out very easily, and a plate-like material corresponding to the thickness of the wafer from the separation starting point is formed into a hexagonal single crystal. The hexagonal single crystal wafer 27 can be easily formed by peeling off from the crystal ingot 11 easily.

2 Laser processing device 11 Hexagonal single crystal ingot 11a First surface (surface)
11b Second side (back side)
13 First Orientation Flat 15 Second Orientation Flat 17 First Surface Normal 19 c-axis 21 c-plane 23 Modified Layer 25 Crack 26 Support Table 30 Laser Beam Irradiation Unit 36 Condenser (Laser Head)
60 Water tank 62 Ultrasonic device 64 Pure water

Claims (3)

  1. A hexagonal crystal having a first surface, a second surface opposite to the first surface, a c-axis extending from the first surface to the second surface, and a c-plane orthogonal to the c-axis A method of producing a wafer for producing a wafer from a single crystal ingot,
    The condensing point of a laser beam having a wavelength that is transmissive to the hexagonal single crystal ingot is positioned at a depth corresponding to the thickness of the wafer generated from the first surface, and the condensing point and the hexagonal single crystal The laser beam is irradiated to the first surface while relatively moving with the crystal ingot, and a separation layer is formed by forming a modified layer parallel to the first surface and a crack extending from the modified layer. A separation origin forming step to be formed;
    After performing the separation starting point forming step, a wafer peeling step of peeling a plate-like material corresponding to the thickness of the wafer from the separation starting point from the hexagonal single crystal ingot to produce a hexagonal single crystal wafer, and
    The separation starting point forming step includes a direction perpendicular to a direction in which the c-axis is inclined by an off-angle with respect to the normal of the first surface and an off-angle is formed between the first surface and the c-plane. A modified layer forming step for forming a linear modified layer by relatively moving the condensing point of the laser beam;
    An index step of relatively moving the condensing point in a direction in which the off-angle is formed to index a predetermined amount,
    In the wafer peeling step, a hexagonal single crystal wafer is produced by immersing a hexagonal single crystal ingot in water and applying ultrasonic waves to peel the plate from the hexagonal single crystal ingot. Generation method.
  2.   In the separation starting point forming step, a laser beam condensing point is positioned on the formed modified layer, and the modified layer is irradiated with the laser beam a plurality of times to separate the modified layer from the crack. The method for producing a wafer according to claim 1.
  3.   The method for producing a wafer according to claim 1 or 2, wherein the hexagonal single crystal ingot is selected from a SiC ingot or a GaN ingot.
JP2015001040A 2015-01-06 2015-01-06 Wafer generation method Active JP6391471B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2015001040A JP6391471B2 (en) 2015-01-06 2015-01-06 Wafer generation method

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
JP2015001040A JP6391471B2 (en) 2015-01-06 2015-01-06 Wafer generation method
KR1020150171630A KR20160084800A (en) 2015-01-06 2015-12-03 Wafer producing method
TW104141114A TWI662612B (en) 2015-01-06 2015-12-08 Wafer generation method
SG10201510273SA SG10201510273SA (en) 2015-01-06 2015-12-15 Wafer producing method
CN201511008904.XA CN105750741B (en) 2015-01-06 2015-12-29 Wafer generation method
US14/988,378 US9925619B2 (en) 2015-01-06 2016-01-05 Wafer producing method
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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6478821B2 (en) * 2015-06-05 2019-03-06 株式会社ディスコ Wafer generation method
JP2018073874A (en) * 2016-10-25 2018-05-10 株式会社ディスコ Processing method and cutting device of wafer
US10562130B1 (en) 2018-12-29 2020-02-18 Cree, Inc. Laser-assisted method for parting crystalline material
US10576585B1 (en) 2018-12-29 2020-03-03 Cree, Inc. Laser-assisted method for parting crystalline material

Family Cites Families (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5223692A (en) 1991-09-23 1993-06-29 General Electric Company Method and apparatus for laser trepanning
FR2716303B1 (en) 1994-02-11 1996-04-05 Franck Delorme Laser distributed Bragg reflectors to, tunable in wavelength, to virtual diffraction gratings selectively activated.
US5561544A (en) 1995-03-06 1996-10-01 Macken; John A. Laser scanning system with reflecting optics
TW350095B (en) * 1995-11-21 1999-01-11 Daido Hoxan Inc Cutting method and apparatus for semiconductor materials
JP2000094221A (en) 1998-09-24 2000-04-04 Toyo Advanced Technologies Co Ltd Electric discharge wire saw
TWI261358B (en) 2002-01-28 2006-09-01 Semiconductor Energy Lab Semiconductor device and method of manufacturing the same
AT362653T (en) * 2002-03-12 2007-06-15 Hamamatsu Photonics Kk Method for the separation of substrates
US20040144301A1 (en) * 2003-01-24 2004-07-29 Neudeck Philip G. Method for growth of bulk crystals by vapor phase epitaxy
JP3998639B2 (en) * 2004-01-13 2007-10-31 株式会社東芝 Manufacturing method of semiconductor light emitting device
JP2005268752A (en) 2004-02-19 2005-09-29 Canon Inc Method of laser cutting, workpiece and semiconductor-element chip
KR100813350B1 (en) * 2004-03-05 2008-03-12 올림푸스 가부시키가이샤 Laser processing equipment
US20050217560A1 (en) * 2004-03-31 2005-10-06 Tolchinsky Peter G Semiconductor wafers with non-standard crystal orientations and methods of manufacturing the same
KR100854986B1 (en) * 2004-06-11 2008-08-28 쇼와 덴코 가부시키가이샤 Production method of compound semiconductor device wafer
JP4809632B2 (en) * 2005-06-01 2011-11-09 ルネサスエレクトロニクス株式会社 Manufacturing method of semiconductor device
JP4749799B2 (en) 2005-08-12 2011-08-17 浜松ホトニクス株式会社 Laser processing method
JP4183093B2 (en) * 2005-09-12 2008-11-19 コバレントマテリアル株式会社 Silicon wafer manufacturing method
JP5011072B2 (en) * 2007-11-21 2012-08-29 株式会社ディスコ Laser processing equipment
US8338218B2 (en) * 2008-06-26 2012-12-25 Semiconductor Energy Laboratory Co., Ltd. Photoelectric conversion device module and manufacturing method of the photoelectric conversion device module
JP5692969B2 (en) 2008-09-01 2015-04-01 浜松ホトニクス株式会社 Aberration correction method, laser processing method using this aberration correction method, laser irradiation method using this aberration correction method, aberration correction apparatus, and aberration correction program
CN102439728B (en) 2009-04-21 2015-08-19 泰特拉桑有限公司 Form the method for the structure in solar cell
JP5537081B2 (en) 2009-07-28 2014-07-02 浜松ホトニクス株式会社 Processing object cutting method
JP5379604B2 (en) * 2009-08-21 2013-12-25 浜松ホトニクス株式会社 Laser processing method and chip
JP5558128B2 (en) 2010-02-05 2014-07-23 株式会社ディスコ Processing method of optical device wafer
JP2011165766A (en) 2010-02-05 2011-08-25 Disco Abrasive Syst Ltd Method of processing optical device wafer
US8722516B2 (en) * 2010-09-28 2014-05-13 Hamamatsu Photonics K.K. Laser processing method and method for manufacturing light-emitting device
JP5904720B2 (en) 2011-05-12 2016-04-20 株式会社ディスコ Wafer division method
JP5912287B2 (en) * 2011-05-19 2016-04-27 株式会社ディスコ Laser processing method and laser processing apparatus
JP5912293B2 (en) * 2011-05-24 2016-04-27 株式会社ディスコ Laser processing equipment
JP5917862B2 (en) * 2011-08-30 2016-05-18 浜松ホトニクス株式会社 Processing object cutting method
JP6002982B2 (en) 2011-08-31 2016-10-05 株式会社フジシール Pouch container
JP5939752B2 (en) * 2011-09-01 2016-06-22 株式会社ディスコ Wafer dividing method
JP5878330B2 (en) * 2011-10-18 2016-03-08 株式会社ディスコ Laser beam output setting method and laser processing apparatus
JP2014041925A (en) * 2012-08-22 2014-03-06 Hamamatsu Photonics Kk Method for cutting workpiece
JP2014041924A (en) * 2012-08-22 2014-03-06 Hamamatsu Photonics Kk Method for cutting workpiece
JP6090998B2 (en) * 2013-01-31 2017-03-08 一般財団法人電力中央研究所 Method for producing hexagonal single crystal, method for producing hexagonal single crystal wafer
WO2014179368A1 (en) 2013-04-29 2014-11-06 Solexel, Inc. Damage free laser patterning of transparent layers for forming doped regions on a solar cell substrate
JP6390898B2 (en) 2014-08-22 2018-09-19 アイシン精機株式会社 Substrate manufacturing method, workpiece cutting method, and laser processing apparatus
JP6358941B2 (en) 2014-12-04 2018-07-18 株式会社ディスコ Wafer generation method
JP6395613B2 (en) * 2015-01-06 2018-09-26 株式会社ディスコ Wafer generation method
JP6395633B2 (en) 2015-02-09 2018-09-26 株式会社ディスコ Wafer generation method
JP6395634B2 (en) * 2015-02-09 2018-09-26 株式会社ディスコ A method of generating a wafer
JP6425606B2 (en) 2015-04-06 2018-11-21 株式会社ディスコ Wafer production method
JP6482389B2 (en) 2015-06-02 2019-03-13 株式会社ディスコ Wafer generation method
JP6472333B2 (en) 2015-06-02 2019-02-20 株式会社ディスコ Wafer generation method
JP6482423B2 (en) 2015-07-16 2019-03-13 株式会社ディスコ Wafer generation method
JP6486240B2 (en) * 2015-08-18 2019-03-20 株式会社ディスコ Wafer processing method
JP6486239B2 (en) 2015-08-18 2019-03-20 株式会社ディスコ Wafer processing method

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